Speed-controlling device applicable to electric motors and generators.



D. BALAGHOWSKY a; P.' CAIRE.

SPEED GONTROLLING DBVGE APPLICABLE T0 BLEGTRIG MOTORS AND GBNERATORS.

APPLICATION FILED MAY 8,1907.

950,?74.. Patented June 7', 1910.

DMITRY BALACI-IOWSKY, OF PARIS, AND

PHILIPPE CAIRE, OF LEVALLOIS-PARIS,

FRANCE.

SPEED-CONTROLLING DEVICE APPLICABLE To all whom fit may concern:

Be it known that we, DMITRY BALACHOW- SKY, a subject of the Emperor ofRussia, and resident of Paris, France, and PHILIPPE CAIRE, a citizen ofthe Republic of France, and resident of Levallois-Paris, France, haveinvented a new and useful Speed-Controlling Device Applicable toElectric Motors and Generators, which speed-controlling device is fullyset forth in the following specilication.

This invention relates to an improved device for regulating shunt-woundmotors with the object of obtaining variation of speed or torque withoutvarying the voltage of the feed current. This object is accomplished byemploying a coil of varying` cross-section to excite the held-magnets,and with a novel arrangement for varying the eective current in saidcoil. This arrangement is suitable also for varying the voltage ofshuntwound generators, and as the connections for the motor and thegenerator are the same, the connections are described only as applied toa motor.

In the drawing the figure is a diagrammatic representation of theregulator applied to a motor.

The field exciting coil a c of the motor M is shunted across the feedwires of the generator G. This exciting coil comprises a portion a Z) offine wire and a portion Z) c of thicker winding, preferably increasingin cross-section from I) to c.

The poles of the armature of the motor are connected to the feed wiresfrom the generator at e and o, but the portion o 7c p of the connectionbetween the motor and the point 0 is made of variable resistance, asdiagrammatically indicated. The point lo is connected by a movablecontact it to any point along the coil l) c.

With the resistance of the portion 0 7c p constant and the contact it atthe point c, movement of the contact L toward l) permits a portion ofthe motor-armature current to pass through the exciting coils between cand h. As 71, moves farther toward Z), this portion of the armaturecurrent passes through more of the exciting coils increasing the eldmagnetism and, since the resistance of the coils c Z) is not great,increasing the Specification of Letters Patent.

Application filed May 8, 1907.

TO ELECTRIC MOTORS AND GENERATORS.

Patented June 7, 1910.

serial No. 372,577.

torque and decreasing the speed of the motor armature.

Then the contact it has reached the point ZJ, the field magnetism may befurther increased by increasing the resistance of the portion o lc p andthus diverting more of the motorarmature current through the coils b c.

The greatest field magnetization and the greatest armature torque occurswhen the contact 71, is at the point I) and the resistance of theportion 0 /c p is the maximum. The least field magnetization and highestmotorspeed occurs when the contact is at the point c.

Having thus described our invention, we claim as new and desire tosecure by Letters Patent:

l. In an electrical machine, the combination of an armature, an exciterwinding of varied cross-section through which there is a continuous flowof current having a series of contact points, a branch contact toconnect one pole of the armature with the exciter winding at any one ofsaid points, and means for regulating the amount of current flowingthrough the thickest portion of the exciting winding comprising avariable resistance connected in parallel with said winding.

2. In an electrical machine, the combination of a pair of feed-wires, afield exciting winding having a finer winding at one end and a thickerwinding of varied cross section at the other end provided with a seriesYof contact points, an armature having one terminal connected to the feedwire to which said fine wire is connected, a conductor of variableresistance connecting the second terminal of the armature to the feedwire to which `the thicker winding is connected, and a movable contactconnecting said second terminal to any of said Contact points of thethicker winding.

In testimony whereof we have signed this specilication in the presenceof two subscribing witnesses.

DMITRY BALACI-IOIVSKY. PHILIPPE CAIRE. Titnesses EMILE LEDRET,

DEAN B. MASON.

